• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.415-427
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• 1993

The purpose of this study was to evaluate the thermoregulatory responses to postures under different environmental conditions and to obtain the basal information for standard clothing weight, indoor climates, and working condition. Two adult female (22.5yrs, 46kg) were participated in this study. The experimental conditions were divided into three groups ; 1) comfort($27{\pm}1^{\circ}C$, $60{\pm}10%$), 2) hot($34{\pm}1^{\circ}C$, $60{\pm}10%$), and 3) cold($21{\pm}1^{\circ}C$, $50{\pm}10%$) condition. The postures performed were as follows; standing, sitting on the chair, sitting on the floor, and supine on the floor. At each condition, subjective sensations, 12 points skin temperature, rectal temperature, total and local sweat rate, pulse rates, blood pressure, skin blood flow rate were measured. The results were as follows : 1. Rectal temperature was high significant among groups in order of supine, sitting on the floor, sitting on the chair, standing posture(p<0.01). 2. Skin temperature was high in part of contact with the surface of the floor or wall and the effect of posture was greater in peripheral temperature than torso temperature. Sitting on the chair and sitting on the floor posture showed higher peripheral temperature than standing and supine posture. And peripheral temperature was lower in supine posture than any other postures. 3. Total and local sweat rate were decreased in order of standing, sitting on the chair, sitting on the floor, supine posture. 4. Pulse rate and disastolic blood pressure were higher in standing posture than supine posture, and there was significant difference between two postures(p<0.001). 5. Blood flow rate of thigh was high in sitting on the chair and sitting on the floor posture and low in standing posture. Blood flow rate of leg was low in standing posture significantly(p<0.01). 6. In comfort and hot condition, temperature sensation and comfort sensation were higher in standing posture and lower in supine posture than any other postures. In cold condition, temperature sensation was lower and comfort sensation was higher in standing and supine posture than any other postures. And supine posture was appeared positive in hot condition and negative in cold condition. From this study, we confirmed the effects of posture on human thermoregulatory responses. Results indicate that even under same conditions and clothing weight, the insulation of clothing will be different to postures.

• Korean Journal of Ecology and Environment
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• v.40 no.3
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• pp.387-394
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• 2007

Despite geographic barriers such as oceans, many freshwater algal species inhabit different continents of the world. A unicellular freshwater alga, Mallomonas caudeata, commonly occurring in Asia, Europe, and America of the northern Hemisphere, is closely related to human life such as monitoring blooms and defecting changes in climates. In order to demonstrate its occurrence in Korea and to infer its phylogeny, we sequenced nuclear SSU and plastid rbcL genes from isolates collected in six different reservoirs. We have also investigated transmission electron microscopy of the Korean isolates. SSU sequences of the species from Korea and USA were almost identical, having pair-wise divergences of 0.06% in SSU and 0.45% in rbcL. Both gene trees revealed that the species was clearly separated from other species of the genus, while the genus was not monophyletic. Rhizoplasts are composed of microfibrils organised in striated rootlets attached to the multilayered plate of basal bodies and arranged on the surface of the nucleus at their distal ends. The rhizoplast constitutes a basal body-nucleus connector similar to that of typical Synurophyceas. The results that Mallomonas was not supported by both SSU and rbeL data sets require a further study with additional taxon sampling.

• Ocean and Polar Research
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• v.41 no.2
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• pp.89-97
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• 2019

Long chain plant waxes (n-alkanes, n-alkanoic acids, and n-alcohols) and their carbon isotopic compositions (${\delta}^{13}C$) in geologic archives are valuable tools for paleovegetation reconstruction. However, the sensitivity of different plant wax constituents to vegetation shift is not well understood. This study explores controls on the variation in ${\delta}^{13}C$ values of long-chain n-alkanes ($C_{27}$ to $C_{33}$) and n-alkanoic acids ($C_{26}-C_{30}$) in the Gulf of Mexico core sediments (ODP 625B) near the Mississippi River delta. n-Alkanoic acids' ${\delta}^{13}C$ values were higher than those of n-alkanes by 1-2‰ on average and such a pattern is the opposite from their isotope fractionation observed in living plants: 1-2‰ smaller in n-alkanes than n-alkanoic acids. We attribute this offset to contributions from aquatic plants or microbes that produce high concentrations of $^{13}C-enriched$ long-chain n-alkanoic acids. The sensitivity of n-alkanes and n-alkanoic acids to vegetation and climate varied among chain lengths. The $n-C_{33}$ alkanes were most sensitive to $C_4$ grassland expansion among n-alkane homologues, while no specific trend was observed in n-alkanoic acids. This is due to the similarity in n-alkanoic acid concentrations between $C_3$ and $C_4$ plants by homologues and low terrestrial plant-derived n-alkanoic acid contributions to the sediments. The results of this study suggest that long chain n-alkanoic acids' ${\delta}^{13}C$ values in sediments may be influenced by contributions from different sources such as aquatic plants or microbial inputs and therefore interpretations regarding this matter should be cautiously formulated. We suggest that there is a need for further studies on characterizing long-chain n-alkanoic acids ($C_{26}-C_{34}$) in aquatic plants and microbes from various climates and environments in order to investigate their production and integration into sedimentary archives.

• Journal of the Korean earth science society
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• v.32 no.7
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• pp.750-760
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• 2011

In this study, the reproducibility of the simulated current climate by using two regional climate models, such as Seoul National University Regional Climate Model (SNURCM) and Weather Resuearch and Forecasting (WRF), is evaluated in advance to produce the standard regional climate scenario of future climate. Within the evaluation framework of a COordinated Regional climate Downscaling EXperiment (CORDEX), 28-year-long (1978-2005) regional climate simulation was conducted by using the Hadley Centre Global Environmental Model (HadGEM2-AO) global simulation data of the National Institute of Meteorological Research (NIMR) as a lateral boundary forcing. The simulated annual surface temperatures were in good agreement with the observation; the spatial correlation coefficients between each model and observation were over 0.98. The cold bias, however, were shown over the northern boundary in the both simulated results. In evaluation of the simulated precipitation, the skill was reasonable and good. The spatial correlation coefficients for the precipitation over the land area were 0.85 and 0.79 in SNURCM and WRF, respectively. It is noted that two regional climate models (RCMs) have different characteristics for the distribution of precipitation over equatorial and midlatitude areas. SNURCM shows better distribution of the simulated precipitation associated with the East Asia summer monsoon in the mid-latitude areas, but WRF shows better in the equatorial areas in comparison to each other. The simulated precipitation is overestimated in summer season (JJA) rather than in spring season (MAM), whereas the spatial distribution of the precipitation in spring season corresponds to the observation better than in summer season. Also the RCMs were capable of reproducing the annual variability of the maximum amount and its timing in July, in which the skills over the inland area were in better agreement with the observation than over the maritime area. The simulated regional climates, however, have the limitation to represent the number of days for extremely hot temperature and heavy rainfall over South Korea.

• Journal of the Ergonomics Society of Korea
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• v.36 no.1
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• pp.23-36
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• 2017

Objective: This paper presents a study to evaluate the WBGT index for assessing the effects of a wide range of outdoor weather conditions on human responses. Background: The Wet Bulb Globe Temperature (WBGT) index was firstly developed for the assessment of hot outdoor conditions. It is a recognised index that is used world-wide. It may be useful over a range of outdoor conditions and not just for hot climates. Method: Four group experiments, involving people performing a light stepping activity, were conducted to determine human responses to outside conditions in the U.K. They were conducted in September 2007 (autumn), December 2007 (winter), March 2008 (spring) and June 2008 (summer). Environmental measurements included WBGT, air temperature, radiant temperature (including solar load), humidity and wind speed all measured at 1.2m above the ground, as well as weather data measured by a standard weather station at 3m to 4m above the ground. Participants' physiological and subjective responses were measured. When the overall results of the four seasons are considered, WBGT provided a strong prediction of physiological responses as well as subjective responses if aural temperature, heart rate and sweat production were measured. Results: WBGT is appropriate to predict thermal strain on a large group of ordinary people in moderate conditions. Consideration should be given to include the WBGT index in warning systems for a wide range of weather conditions. However, the WBGT overestimated physiological responses of subjects. In addition, tenfold Borg's RPE was significantly different with heart rate measured for the four conditions except autumn (p<0.05). Physiological and subjective responses over 60 minutes consistently showed a similar tendency in the relationships with the $WBGT_{head}$ and $WBGT_{abdomen}$. Conclusion: It was found that either $WBGT_{head}$ or $WBGT_{abdomen}$ could be measured if a measurement should be conducted at only one height. The relationship between the WBGT values and weather station data was also investigated. There was a significant relationship between WBGT values at the position of a person and weather station data. For UK daytime weather conditions ranging from an average air temperature of $6^{\circ}C$ to $21^{\circ}C$ with mean radiant temperatures of up to $57^{\circ}C$, the WBGT index could be used as a simple thermal index to indicate the effects of weather on people. Application: The result of evaluation of WBGT might help to develop the smart clothing for workers in industrial sites and improve the work environment in terms of considering workers' wellness.

• Research in Plant Disease
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• v.26 no.3
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• pp.159-169
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• 2020

Pectobacterium carotovorum subsp. carotovorum (Pcc) causes bacterial soft rot on a wide range of crops worldwide, especially in countries with warm and humid climates. This study was conducted to establish an efficient screening method for resistant cultivars of Chinese cabbage to bacterial soft rot. Resistance degrees of 65 commercial Chinese cabbage cultivars to the Pcc KACC 10225 isolate were investigated. For further study, three Chinse cabbage cultivars (Taebong, Hadaejangkun, CR Alchan) showing different level of resistance to the bacterium were selected. The development of bacterial soft rot on the cultivars was tested according to several conditions such as growth stage of Chinse cabbage seedling, inoculum concentration, and incubation temperature after inoculation. On the basis of the results, we suggest that an efficient screening method for resistant Chinses cabbage to Pcc is to inoculate twenty one-day-old seedlings with a bacterial suspension of Pcc at a concentration of 1×10⁷ cfu/ml, and to incubate the plants in a dew chamber at 25℃ for 24 hr and then to cultivate in a growth room at 25℃ and 80% relative humidity with 12-hr light per day.

• Asian Journal of Turfgrass Science
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• v.25 no.1
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• pp.43-47
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• 2011

Creeping bentgrass (Agrosis stolonifera L.) is regarded to be the most widely used cool-season turf grass species grown on golf greens and fairways in temperate climates of North America. Creeping bentgrass is highly susceptible to the fungal disease 'dollar spot' caused by Sclerotinia homoeocarpa. Dollar spot is a foliar disease favored by conditions of high humidity, warm days, and cool nights. Studies using Aliette Signature (Fosetyl Aluminum formulated with a green pigment) mixed with another broad-spectrum fungicide do not always provide additional visual quality benefits compared to the fungicide alone. The exact mechanism for improved summer visual quality, when it occurs, is not known. Fertility management and environment likely contribute. The object of this study is to evaluate fungicide strategies for control of dollar spot and effect on visual quality during summer and on an L-93/G-2 creeping bentgrass green. Nine fungicide combinations were used for this study. Disease control and visual quality by fungicides was evaluated on an established G-2/L-93 creeping bentgrass green at 3-hole Sunshine Golf Course in Lemont, IL. All fungicide combination showed excellent dollar spot suppression except Fore throughout the study. Visual quality of greens by addition of Aliette Signature is enhanced when bentgrass growth is compromised and slow. Dollar spot levels in Fore plots increased to 30% on 14 August, and was no different than untreated plots. Unacceptable quality by Fore was due to lack of dollar spot control.

• Journal of the Ergonomics Society of Korea
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• v.36 no.3
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• pp.169-181
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• 2017

Objective: The aim of this study was to explore the influence of outdoor weather conditions on subjective responses during physical activity. Background: The largest difference between indoor and outdoor conditions is the existence of the sun. The heat load from the sun has an influence on the heat gain of the human body and the intense degree of solar radiation affected thermal comfort. Method: Thirty eight people were exposed to a range of climatic conditions in the UK. Weather in England does not have extremely hot and cold temperature, and the current study was conducted under warm (summer and autumn) and cool (spring and summer) climates. Measurements of the climate included air temperature, radiant temperature (including solar load), humidity and wind around the subjects. Subjective responses were taken and physiological measurements included internal body temperature, heart rate and sweat loss. Results: This study was conducted under four kinds of environmental conditions and the environmental measurement was performed in September, December, March, and June. The values for sensation, comfort, preference, and pleasantness about four conditions were from 'neutral' to 'warm', from 'not uncomfortable' to 'slightly comfortable', from 'slightly cooler' to 'slightly warmer', and from 'neither pleasant nor unpleasant' and 'slightly unpleasant', respectively. All subjective responses showed differences depending on air temperature and wind speed, and had correlations with air temperature and wind speed (p<0.05). However, subjective responses showed no differences depending on the radiant temperature. The combined effects of environmental parameters were showed on some subjective responses. The combined effects of air temperature and radiant temperature on thermal sensation and pleasantness were significant. The combined effects of metabolic rate with air temperature, wind speed and solar radiation respectively have influences on some subjective responses. In the case of the relationships among subjective responses, thermal sensation had significant correlations with all subjective responses. The largest relationship was shown between preference and thermal sensation but acceptance showed the lowest relationship with the other subjective responses. Conclusion: The ranges of air temperature, radiant temperature, wind speed and solar radiation were $6.7^{\circ}C$ to $24.7^{\circ}C$, $17.9^{\circ}C$ to $56.6^{\circ}C$, $0.84ms^{-1}$ to $2.4ms^{-1}$, and $123Wm^{-2}$ to $876Wm^{-2}$ respectively. Each of air temperature and wind speed had significant relationships with subjective responses. The combined effects of environmental parameters on subjective responses were shown. Each radiant temperature and solar radiation did not show any relationships with subjective responses but the combinations of each radiant temperature and solar radiation with other environmental parameters had influences on subjective responses. The combinations of metabolic rate with air temperature, wind speed and solar radiation respectively have influences on subjective responses although metabolic rate alone hardly made influences on them. There were also significant relationships among subjective responses, and pleasantness generally showed relatively high relationships with comfort, preference, acceptance and satisfaction. Application: Subjective responses might be utilized to predict thermal stress of human and the application products reflecting human subjective responses might apply to the different fields such as fashion technology, wearable devices, and environmental design considering human's response etc.

• Nuclear Engineering and Technology
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• v.44 no.5
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• pp.523-534
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• 2012

The objective of this study was to experimentally investigate the effect of heat curing methods on the temperature history and strength development of slab concrete exposed to $-10^{\circ}C$. The goal was to determine proper heat curing methods for the protection of nuclear power plant structures against early-age frost damage under adverse (cold) conditions. Two types of methods were studied: heat insulation alone and in combination with a heating cable. For heat curing with heat insulation alone, either sawdust or a double layer bubble sheet (2-BS) was applied. For curing with a combination of heat insulation and a heating cable, an embedded heating cable was used with either a sawdust cover, a 2-BS cover, or a quadruple layer bubble sheet (4-BS) cover. Seven different slab specimens with dimensions of $1200{\times}600{\times}200$ mm and a design strength of 27 MPa were fabricated and cured at $-10^{\circ}C$ for 7 d. The application of sawdust and 2-BS allowed the concrete temperature to fall below $0^{\circ}C$ within 40 h after exposure to $-10^{\circ}C$, and then, the temperature dropped to $-10^{\circ}C$ and remained there for 7 d owing to insufficient thermal resistance. However, the combination of a heating cable plus sawdust or 2-BS maintained the concrete temperature around $5^{\circ}C$ for 7 d. Moreover, the combination of the heating cable and 4-BS maintained the concrete temperature around $10^{\circ}C$ for 7 d. This was due to the continuous heat supply from the heating cable and the prevention of heat loss by the 4-BS. For maturity development, which is an index of early-age frost damage, the application of heat insulation materials alone did not allow the concrete to meet the minimum maturity required to protect against early-age frost damage after 7 d, owing to poor thermal resistance. However, the combination of the heating cable and the heat insulating materials allowed the concrete to attain the minimum maturity level after just 3 d. In the case of strength development, the heat insulation materials alone were insufficient to achieve the minimum 7-d strength required to prevent early-age frost damage. However, the combination of a heating cable and heat insulating materials met both the minimum 7-d strength and the 28-d design strength owing to the heat supply and thermal resistance. Therefore, it is believed that by combining a heating cable and 4-BS, concrete exposed to $-10^{\circ}C$ can be effectively protected from early-age frost damage and can attain the required 28-d compressive strength.

• Research in Plant Disease
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• v.24 no.3
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• pp.193-201
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• 2018

Pectobacterium carotovorum subsp. carotovorum (Pcc) causes bacterial soft rot on a wide range of crops worldwide, especially in countries with warm and humid climates. This study was conducted to establish an efficient screening method for resistant cultivars of radish (Raphanus sativus) to bacterial soft rot. Resistance degrees of 60 commercial radish cultivars to the Pcc KACC 10421 isolate were investigated. For further study, six radish cultivars (Awooriwoldong, YR Championyeolmu, Jeonmuhumu, Bitgoeunyeolmu, Sunbongaltari, Housecheongok) showing different level of resistance to the bacterium were selected. The development of bacterial soft rot on the cultivars was tested according to several conditions such as incubation temperature, seedling stage of radish, inoculum concentration to develop the disease. On the basis of the results, we suggest that an efficient screening method for resistant radish to Pcc is to inoculate twenty-day-old seedlings with a bacterial suspension of Pcc at a concentration of $8{\times}10^5cfu/ml$ and then to cultivate the plants in a growth room at $25^{\circ}C$ and 80% RH with 12-hour light per day.